Problem: camera will not power up using attached battery (charged - checked on another camera)

Known facts

1. Camera works perfectly when running off the mains adapter

2. Orange light shows when charging and goes out when battery is charged - battery is charged

3. When charging, on activation of the battery indicator it displays the thermometer scale
showing 0% - never changes even when fully charged

4. Remove the battery and the battery indicator is not displayed - therefore camera sensing
that a battery is attached

5. Only occasionally the camera will power on with the battery attached but indicates Battery Low
and then switches off

6. It is not the battery as I have bought a replacement and this does the same.

Any suggestions for correcting this problem would be gratefully received!

I have some electronics experience and therefore would be willing to take the camera apart if there is a known solution.